Long draft spinning apron



June 18, 1946. M BAQQN T 2,402,356

I LONG DRAFT SPINNING APRON Original Filed June I 6 1942 ATTORNEYS Patented June 18, 1946 Dayton, Ohio, assignors to The Dayton Rubber Manufacturing Company, Dayton, Ohio, a corporation of Ohio Original application June '6, 1942, Serial No.

446,120. Divided and this application .1943, Serial No. 433,090

8 Claims. (01. 19-131) This invention relates to textile drafting machinery, and more particularly deals with draft aprons and method for their manufacture.

In textilespinnlng machines comprising fiber drafting mechanism an endless belt or band is used as a conveyer to carry the flbe'r's along during.

the drafting stage. II

.In modern drafting machinery the so-called long draft method is employed. In the Casablanca system two aprons run together. At one end the aprons go over rotating arbors and at the other end over fixed metal bars. -The two aprons,

through their cushioning and frictional power;

April 15,

fiber composition which is of substantially uniform gauge thickness throughout, which possesses the proper coefllcient of friction at its surface to carrythe fibers along through the drafting unit in a uniformly straight'line, and which will operate in unisonwith the-rest of the machine so that slippage is not encountered.

In the long draft apron which is the subject matter of the aforementioned copending application, the synthetic rubber or synthetic resin composition is reinforced with .thin textile fibers laid substantially parallel to each other and along the act as holding media and regulate the feed to the front drafting rolls of the machine.

The two arbors in the Casablanca system over which the draft aprons are positioned are dissimilar in the sense that one is the driven roll longitudinal axis of the apron. This fiber reinforcing, extending lengthwise of the circumference or periphery of the apron, serves to produce a longitudinally inextensible apron having a coeillcient of friction suitable to prevent slippage during operation. Theresuits obtained with while the other generally has a knurled surface I and is the driving roll. The knurled surface cuts into the inner surface of the apron passing over it and the outer surface of the apron engages the outer surface of the apron passing over the smooth surfaced roll and causes the movement thereof. I I

As has been noted hereinbefore, the aprons are rubbed constantly over rigid metal bars, and a satisfactory apron is considered to be one which does not exhibit a tendency to heat, chafe, or bind in passing over the fixed metal bars.

When the various types of drafting systems were developed leather was the only material available for-aprons. The service was so severe that only specially processed leather could beemployed. Even this specially selected and 8136-.

cially treatedleather failed to give complete satisfaction, and for some time there was a definite need for a better type of apron.

.As is known to those skilled in the art, aprons of rubber composition have been introduced in recent years as substitutes for the orthodox leather apron. These rubberaprons offer some advantage but have. failed to overcome many of the disadvantages of the earlier leather aprons.v

More recently, special types of rubber composition have been devised or deveiopedjand long and vastly superior to the earlier type of leather such an apron are far superior to those hitherto obtained with aprons made of rubber composition apron. However the reinforcing fibers, particu iarly those lying near thefi-ber working surface, have a tendency to become exposed and to pick up lint, resulting in a. dirty apron, but one which nevertheless performs satisfactorily otherwise.

The present invention deals with an improved method for producing a long draft apron which is free from the disadvantages which remain-ed in the long draft apron which isthe subject of the aforementioned copending application. The apron which is the product of the present invention is a cord reinforced apron. By the use of cords laid parallel and along the longitudinal axis of the apron, an apron is obtained which is sub I stantially inextensible and yet does not have a tendency of dirtying up by picking up lint.

. The nature of the present invention will be understood from the following description taken in'connection with the annexed drawing wherein: I v l lg. 1 is a diagrammatic view of a typical Casablanca type draftin system showing the two draft aprons made with such improved rubber composition have successfully coped with some I of'the problems; however, there have remained others. I

In copending application Serial No. 349,517, filed August 2, 19:40, by Joseph Rockofl', there has I been disclosed and claimed an improved long draft apron madecf a combined synthetic rubber and fiber composition or of a synthetic resin and aprons in position; I I

Fig. 2 is-'a diagrammatic view of a typical Saco-Lowell type drafting system showing the single apron in position;

Fig. 3 is a cross sectional view of one form of the draft apron of. our invention in which the cords are. embedded between layers of rubber composition one 'of'which layers is reinforced with fine textile fibers lying substantially parallei to each other and transverse of the longitudinal axis of the draft apron;

Fig. 4 is a diagrammatic view illustrating the 3 method of manufacturing one form of the draft apron of the present invention;

Fig. 5 is a diagrammatic view illustrating the method of manufacturing another form of the draft apron of the present invention;

Fig. 6 is a perspective view, partly in cross section, illustrating the construction of one form of the draft apron of the present invention;

Fig. 7 is a cross sectional view taken along the line I-| of Fig. l and illustrating the manner in which the cords in the two aprons separate to permit the passage of lumps in the fiber. without'curling the apron or' placing thereon undue stresses; and

Fig. 8 is a cross sectional view of another form of the draft apron of our invention in which the cords lie adjacent the inner surface of the apron.

Referring now to the drawing in detail, I is the driving roll having a knurled surface in a typical Casablanca system; H is the driven roll having a smooth surface; I! and is are the fixed metal bars; and I4 and it are the draft aprons, the former passing over the roll Ii and fixed bar I! and the latter passing over the roll. II and fixedbaril.

The manner in which one form of the draftapron of this invention is produced is illustrated in Fig. 4. On the surface of a rotating cylinder. generally designated as ll, there is deposited a thin film or layer of synthetic rubber composition or synthetic resin and then there is applied thereover a winding of cord. After the cord has been applied a second film or layer of rubber composition is applied thereover, whereby the cords, become thoroughly covered and impregnated with the synthetic rubber or synthetic resin composition. Then there is applied thereover a heavier layer of synthetic rubber or synthetic resin composition and the whole vulcanized to produce a unitary draft apron'comprising synthetic rubber or synthetic resin composition reinforced with cords in which the cord layer lies remote from the working surface of the apron and adjacent the inner surface of the apron. A gross sectional view of such an apron is shown in The application of the thin film or layer of synthetic rubber or synthetic resin composition beneath and above the cord layer to impregnate the cord may be carried out in any desirable or advantageous manner. For example, it is possible to spray the films or layers on the surface of the roll II. It is also possible to form a thin tube by extrusion, to apply it as a sleeve over the roll II, to apply the cord layer thereover, and then to continue the operation. This method, however, is not quite advantageous when the thickness of the layer beneath the cord is to be small.

In Fig. there is illustrated a method whereby a draft apron such as shown in Figs. 8 and 6 may be made; and it is to this particular type of apron that the present application is directed. In this case, since the thickness of the underlayer of synthetic rubber or synthetic resin composition is relatively thicker than in the draft apron illustrated in Fig. 8, it proves more advantageous to form the previously mentioned tube of synthetic rubber, or resin composition by extrusion and to Place it as. a sleeve over the surface of the cylinder ii. However, a spraying method could be used with equal satisfaction if it-should be preferred or desired. or the layer or layers of rubber composition could be applied by winding around the drum.

Assuming that the method to be employed involves the use of a tube or extruded member, it is placed over the cylinder it, a cord layer is placed thereover, and then the second layer of synthetic rubber or synthetic resin composition isv deposited over the cord layer in any suitable manner. The built-up body is then vulcanized to produce a unitary structure in which the cord layer lies substantially in the center of the structure.

It will be understood by those skilled in the art that in making the draft apron illustrated in Figs. 3 and 6 the underlayer of rubber composition is reinforced with fine textile fibers and the outer or fiber working layer-is not. Such a draft apron not only possesses the inextensibility imparted to it by the reinforcing cords but also exhibits the property of lateral or transverse rigidity. This type of construction is particularly advantageous because the draft apron exhibits no circumferential stretch and at the same time it retains its shape laterally particularly in the thinner gauges. When aprons of thin gauge are employed which do not include this lateral reinforcement they exhibit a tendency to stretch laterally and to curl and become distorted along the edges. When there is lateral stretch, the width of the apron increases, and this causes the apron to climb the flanged edges of the idler rolls which are used in some typesof drafting machinery and to become permanently distorted.

One marked advantage which is inherent to the construction illustrated in Figs. 3 and 6 is illustrated in Fig. '7. In Figs. 3, 6 and 7 the outer or fiber working layer of the apron is numbered H, the reinforcing cords are numbered II and the fiber reinforced inner layer is numbered it, and the same parts are identified by the same numbers in Fig. 5. In Fig. 8 the outer or fiber working layer of the apron is numbered 20. the cords are numbered 2!, and the inner layer is numbered 22. The same numerals are employed to illustrate the same parts in Fig. 4.

Referring particularly to Fig. 7 which illustrates two draft aprons in cross section. While drafting fibers, it will be noted that the structure of the apron of the present invention is such that it permits yielding of the apron body to permit lumps, hard ends and impurities to pass therethrough without imposing on the apron undue stresses which would ultimately cause damage. It will be noted that the cords numbered it. have split apart to permit the passage of a hard lump 2! found in the fiber layer 14 that is being drafted. This ability to'permit the passage of lumps, hard ends and impurities without damage to the apron is one of the outstanding and most valuable features of the apron illustrated in Figs.

3 and 6, and it is to this particular form of the apron of our invention that the present application is directed. 1

While we have made specific reference to the Casablanca system and the Saco-Lowell system, it will be understood by those skilled in the art that the draft apron of .our invention offers extraordinary advantages when used in other types of textile working machinery wherein draft aprons are employed. These include the Whitin system, the Roth system, and others whichare known to those skilled in the art. Those skilled in the art will understand that in the manufacture of the draft apron of our invention, after the apron body has been built up on the surface of the cylinder II and vulcanized, the surface of the built-up vulcanized body must be smoothed down by abrading or otherwise to provide a perfectly smooth surface free from burrs and projections but without a high polish or shine. In other words, it is desirable'to have abody which is uniform in outside diameter and which possesses a slightly rough but uniform surface. Obviously the built-up body is cut into coefllcient of friction; favorable aging properties;

such as maintenance of their thickness; resistance to cracking, therefore a long life: substantial freedom from static; resistance to oil andto abrasives; stability of length and width; and

freedom from deformation or tackiness when subjected to the temperature and high humidity conditions present in drafting operations.

The draft apron of our invention illustrated in Figs. 3 and 6, because of its transversely dis-x posed fibers on the underlayer of rubber composition, has the ability of causing the reinforcing cords to maintain their original relative position with respect to eachother. This is a characteristic inherent to the structureillu'strated in Figs. 3 and 6 and a point of superiority'over the structure illustrated in Fi 8.

In order to obtain a draft apron exhibiting the desirable characteristics which have been set forth hereinbefore, we have found that certain types of synthetic rubber and synthetic resin compositions prove eminently well adapted. The following are example'sof the synthetic rubber and synthetic resin type of compodtions which maybe used, but it will be understood that our invention is not intended to be limited to the use of these compositions.

Common #1 Using neoprene Vulcanizing: minutes at 300 F. steam cure.

' Courosrrron #2 I I Using Perbunan Perbunan (butadiene acrylic nitrile poly- -Soft Glyptal resin Common Using Flexible Glyptal (polyhydric alcoholphthalic anhydride condensation product) (General Electric 1353U Resin) parts by weight 89 Neoprene binder 1 ,.do 10 Flexible Bakelite resin parts 1 Vulcanizing: 120 minutes at 300 F. dry heat.

The neoprene binder mentioned in the immediately above formula is preferably composed of the following materials Parts by weight Neoprene type E L Litharge 10.07 Sulfur .603 Wood rosin 6.15 Neozona "D" (phenyl-beta-naphthylamine) zinc oxide .1... 6.03 Cumar 8.32 Medium oil- 8.32

When an apron such as illustrated in Figs. 3 and 6 is desired, the fiber-reinforced portion thereof may be compounded according to any of the compositions #1 to, #4 above set forth with the addition thereto of approximately 30 parts 1 by weight of cotton fibers or other suitable fibrous material in finely divided form.

This application is a division'of copending application Serial No. 446,120, filed June 6, 1942.

gIt will be understood that while, we have described certain specific embodiments of our invention, we do not intend to have our invention limited to or circumscribed by the specific defact that our invention is susceptible to modificadisclosure and the scope of the appended claims.

, Parts by weight w Neoprene type G (polymerized chloroprene) 10o Zinc oxide 10 Light magnesium oxide 10 Cumar r I 2 Whiting 20 Cotton seed oil 5 tions without departing from the spirit of this We claim: 1. As a new article ofmanufacture, a draft apronfor textile machinery comprising'an outer layer having a fiber working surface, an inner layer having a driving surface and an intermediate layer of rubber-like material reinforced with cord extending longitudinally of the apron, said inner layer being'composed of rubber-like material reinforced with short finely divided textile fibers which lie substantially parallel to each other and transverse of the longitudinal axis of, the apron, said outer layer consisting of rubberlike material.

2. As a new article of manufacture, a draft apron for textile machinery comprising an outer layer having a fiber working surface, an inner layer having a driving surface, and an intermediate layer of polymerized chloroprene reinforced with cord extending longitudinally of the apron, said inner layer being composed of polymerized chloroprene reinforced with short finely divided textile fibers which lie substantially parallel to each other and transverse of the longitudinal axis of the apron, said outer layer consisting of polymerized chloroprene.

3. As a new article of manufacture, a draft apron for textile machine'iaz comprising an outer layer having a fiber working surface. an inner merization product) parts by weight Zinc oxide ..'..parts 5 Sulfur do 2 Altax (benzothiazyl disulflde) do 1 Whiting -do 30 Mineral oil do 10 Vulcanizing: 30 minutes at 800 1". steam cure.

Courosrrrou #3 Usina Thiokoi Farts by weight Thiokol type 1'. (olefin polysulnde) 100 Zinc oxide 2 Diphenyl guanidine .10 Altax-- Whiting 20 Stearic acid .50

layer having a driving surface, and an intermediate layer of butadiene acrylic nitrile copolymer reinforced with cord extending longitudinally of the apron, said inner layer being composed of butadlene acrylic nitrile copolymer reinforced with short finely divided textile fibers which lie substantially parallel to each other and trans- Vulcanizing: 30 minutes at 300 F. steam cure. I verse of the longitudinal axis of the apron, said outer layer consisting of butadiene acrylic nitrile copolymer.

4. As a new article of manufacture, a draft apron for textile machinery comprising an outer layer having a fiber working surface, an inner layer having a driving surface, and an intermediate layer of olefin polysulyfide reinforced with cord extending longitudinally of the apron, said inner layer being composed of olefin polysulfide reinforced with short finely divided textile fibers which lie substantially parallel to each other and transverse of the longitudinal axis of the apron, said outer layer consisting of olefin polysulfide.

5. As a new article of manufacture, a draft apron for textile machinery comprising an outer layer having a fiber working surface, an inner layer having a driving surface; and an intermediate layer of rubber-like material reinforced with cords extending longitudinally of the apron, said cords lying substantially equidistantly spaced from the fiber working surface'of said outer layer and the driving surface of said inner layer, said inner layer being composed of, rubber-like material reinforced with short finely divided textile fibers which lie substantially parallel to each other and transverse of the longitudinal axis of the apron, said outer layer consisting of rubberlike material.

6. As a new article of-manufacture, a draft apron for textile machinery comprising an outer layer having a fiber working surface, an inner layer having a driving surface, and an intermediate layer or polymerized chloroprene reinforced with cords extending longitudinally of the apron, said cords lying substantially equidistantly spaced from the fiber working surface of said outer layer and the driving surface of said inner layer, said inner layer being composed of polymerized chloroprene reinforced with short finely divided textile fibers which lie substantially parallel to each other and transverse of the longitudinal axis of the apron, said outer layer consisting of polymerised chloroprene.

7. As a new article of manufacture, a draft apron for textile machinery comprising an outer layer having a fiber working surface, an inner layer having a driving surface, and an intermediate layer of butadiene acrylic nitrile copolymer reinforced with cords extending longitudinally of the apron, said cords lying substantially equidistantly spaced from the fiber working surface of said outer layer and the driving surface of said inner layer, said inner layer being composed of butadiene acrylic nitrile copolymer reinforced with short finely divided textile fibers which lie substantially parallel to each other and transverse of the longitudinal axis of the apron, said outer layer consisting of butadiene acrylic nitrile copolymer.

8. As a new article of manufacture, a draft apron for textile machinery comprising an outer layer having a fiber working surface, an inner.

HENRY M. Bacon.

ABRAHAM L; FREEDLANDER. 

